U.S. Department of Agriculture officials say this is the first update to the plan hardiness zone map since 1990.

The just-released map uses temperatures from a more recent period, and over a longer time span, according to a USDA press release.

“This is the most sophisticated Plant Hardiness Zone Map yet for the United States,” said Dr. Catherine Woteki, USDA Under Secretary for Research, Education and Economics. “The increases in accuracy and detail that this map represents will be extremely useful for gardeners and researchers.”

USDA officials say the new map is also more detailed geographically, taking into account features like a valley or higher ground.

Perhaps that’s why it appears Minnesota communities like Isabella and Aitkin are hot spots in a generally colder region.

The new map also allows for searches by zip code, and you can zoom in for greater detail.

Do you find the USDA zone map useful or is experience the best predictor of gardening success?